'Dancing On Ice' mentor Christopher Dean has slammed Jason Gardiner for ''crossing the line'' when he told head coach Karen Barber her opinion didn't matter earlier in the series

The Olympic ice-skating champion thinks when the famously acid-tongued judge told head coach Karen Barber - who Christopher is now dating - her opinion on the ITV1 show didn't matter earlier in the series, he "went too far".

Speaking of the incident, Christopher said: "Sometimes he crosses the line and that was one of those times. He went too far."

However, he admitted 'Dancing On Ice' on the whole has gone for a harder edge this series as show bosses hoped to "up the game".

He told Radio Times magazine: "That's all happened consciously. We've come to a new studio, a new set, and there was a desire to up the game."

Meanwhile, Christopher's professional skating partner and fellow 'Dancing On Ice' mentor Jane Torvill explained the whole process of the celebrity skating show is more "stressful" for Christopher than her.

She added: "He gets more stressed than I do, tries to take on the lighting, the camera angles, everything. He'll say he's not going to get involved. Yeah right. I can read him like a book."